US8104623B2 - Filtering screen - Google Patents

Filtering screen Download PDF

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Publication number
US8104623B2
US8104623B2 US10/543,042 US54304205A US8104623B2 US 8104623 B2 US8104623 B2 US 8104623B2 US 54304205 A US54304205 A US 54304205A US 8104623 B2 US8104623 B2 US 8104623B2
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United States
Prior art keywords
wires
cloth
warp
screen
rectangular
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Active, expires
Application number
US10/543,042
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English (en)
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US20060081529A1 (en
Inventor
Graham Robertson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Schlumberger UK Holdings Ltd
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United Wire Ltd
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Assigned to UNITED WIRE LIMITED reassignment UNITED WIRE LIMITED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ROBERTSON, GRAHAM
Publication of US20060081529A1 publication Critical patent/US20060081529A1/en
Priority to US13/333,421 priority Critical patent/US8246771B2/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
    • B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
    • B07B1/00—Sieving, screening, sifting, or sorting solid materials using networks, gratings, grids, or the like
    • B07B1/46—Constructional details of screens in general; Cleaning or heating of screens
    • B07B1/4609—Constructional details of screens in general; Cleaning or heating of screens constructional details of screening surfaces or meshes
    • B07B1/4618—Manufacturing of screening surfaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
    • B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
    • B07B1/00—Sieving, screening, sifting, or sorting solid materials using networks, gratings, grids, or the like
    • B07B1/46—Constructional details of screens in general; Cleaning or heating of screens
    • B07B1/4609—Constructional details of screens in general; Cleaning or heating of screens constructional details of screening surfaces or meshes
    • B07B1/4663—Multi-layer screening surfaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
    • B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
    • B07B1/00—Sieving, screening, sifting, or sorting solid materials using networks, gratings, grids, or the like
    • B07B1/46—Constructional details of screens in general; Cleaning or heating of screens
    • B07B1/4609—Constructional details of screens in general; Cleaning or heating of screens constructional details of screening surfaces or meshes
    • B07B1/4672—Woven meshes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10—Methods of surface bonding and/or assembly therefor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10—Methods of surface bonding and/or assembly therefor
    • Y10T156/1052—Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing
    • Y10T156/1062—Prior to assembly
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10—Methods of surface bonding and/or assembly therefor
    • Y10T156/1052—Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing
    • Y10T156/108—Flash, trim or excess removal

Definitions

  • This invention concerns screens such as are fitted to vibrating screening machines, sometimes used as shale shakers to separate solids from fluids. Such machines are of particular application in the oil well drilling industry to separate drilling mud from base fluid after recovery from down-hole during drilling.
  • Filter screens for use in such machines are typically constructed from woven wire cloth.
  • the warp wires are those that run along the length of the roll of wire-cloth as it is woven, and wound around the take-up drum, while the weft wires are those which run across the width of the wire-cloth.
  • Square mesh wire cloth is comprised of nominally identical numbers of warp and weft wires per unit area, and a common wire diameter.
  • a 200# market grade cloth has 200 warp wires per inch and 200 weft wires per inch. Both warp and weft wires are 0.050 mm in diameter.
  • a rectangular mesh is normally woven with more warp wires per unit length than weft wires per unit length, since the time taken to weave a given length of wirecloth is dependent on the number of weft wires.
  • One common type of screen comprises layers of mesh bonded to a support structure (normally referred to as a frame) which is usually generally flat and rectangular in shape, and which contains a number of similarly sized (normally rectangular) openings across which the screen mesh is tensioned.
  • the mesh is supported by the frame and the openings in the frame define a corresponding number of mesh covered windows for filtering the fluid materials.
  • the frame may be of metal but more preferably is of a plastics material particularly GRP and preferably is reinforced internally by a wire or rod framework.
  • Such screens will be referred to as integral screens, that is the mesh and frame are integrated by the bonding of the mesh to the support frame.
  • a jig for making integral screens in which two screens are made at the same time, is described in GB Patent Specification 2,382,037. Such a jig will be referred to as a jig of the type described.
  • hook-strip screen Another common type of screen is a so-called hook-strip screen.
  • a screen consists of generally rectangular sheets of wire cloth (mesh) with hooks along two parallel sides. The sheets are attached by the hooks to a stretching mechanism in the shaker. This stretches the mesh to tension the wire cloth. This is necessary to encourage good solids conveyance across the stretched mesh in use.
  • hook-strip screens are usually stretched over a support which presents a convex upper surface to the mesh so that the mesh in tension becomes convexly curved as shown in FIG. 2 .
  • the tensioning load is applied in one direction only. This means that if the screen is over-tensioned the wires parallel to the tensioning direction will tend to fail before the wires extending in the perpendicular sense. In use, over-tensioning can occur due to excessive solids build-up or any general overloading of the screen, as well as due to any inappropriate tensioning of the mesh during set-up.
  • an integral screen for use in a vibrating machine for separating solids from liquid material comprises woven wire cloth of orthogonal warp and weft wires, tensioned and bonded to a support structure defining a rectangular opening across which the cloth extends, wherein the orientation of the cloth is chosen so that the warp wires extend across the width (i.e. shorter dimension) of the rectangular opening and the weft wires extend across the length (i.e. longer dimension) of the rectangular opening.
  • the rectangular opening in the support structure includes a plurality of similarly dimensioned and orientated and regularly arranged smaller rectangular openings, formed by a lattice of struts criss-crossing the larger opening, the cloth is bonded to the lattice struts as well as the boundary of the larger opening, so that the warp wires are also parallel to the width (i.e. the shorter dimension) of the smaller rectangular openings.
  • a cloth is thought of as having a rectangular mesh if the aspect ratio of the openings in the weave is at least 0.8:1.
  • the warp wires are preferably selected to have a greater cross sectional size than the weft wires, which if they extend perpendicularly relative to the length dimension of the or each opening are able to resist the greater stress across the width of the central region of the or each opening.
  • a cloth is said to have a square mesh if the openings in the weave have an aspect ratio of between 0.9:1 and 1:1.1.
  • the larger warp wires preferably have a cross-sectional area of between 10% and 30% greater than the smaller weft wires.
  • the larger warp wires have a cross-sectional area in the range 20% to 25 % greater than the smaller weft wires.
  • the larger warp wires have a cross-sectional area 22% greater than that of the smaller weft wires.
  • the wires are typically of circular cross-section.
  • the diameter of the larger warp wires is 0.046 mm
  • the diameter of the weft wires is 0.036 mm, and there may be 200 warp wires per inch and 230 smaller weft wires per inch.
  • the diameter of the wires is as before, but there are 212 larger warp wires per inch and 230 smaller weft wires per inch.
  • the rectangular openings in the weave should be aligned with their longer dimension parallel to the direction of solids flow over the screen.
  • the support frame has a plurality of regularly arranged similarly orientated and similarly sized smaller rectangular openings, the longer dimensions of which are parallel to the length dimension of the frame, the solids flow will normally be parallel to the length dimension of the frame, and accordingly it has been considered necessary for the warp wires in the rectangular mesh cloth stretched over the rectangular openings, to run the length of the rectangular openings, to achieve optimum solids conveyance and deblinding.
  • a common overall frame size is of the order of 42′′ ⁇ 30′′ and if 48′′ wide cloth is to be used so that the weft wires extend across the 30′′ dimension, the cloth has to be orientated relative to the frame so that the 48′′ width extends across the 30′′ width of the frame. Accordingly there will be a lot of waste cloth to be cut away from the two longer edges of the frame after bonding.
  • the 48′′ wide cloth is cut to 66′′ length, and laid over the two side by side frames in the jig, with the warp wires perpendicular to the length dimension of the frames and where the frames include smaller rectangular openings, the warp wires are therefore perpendicular to the longer dimension of each of the smaller openings in the frames.
  • the invention thus has the advantage of enabling fully functional and long-life screens to be made using standard 48′′ wide woven wire cloth.
  • the hooks will be positioned along the two parallel edges of the cloth between which the greater cross-section warp wires extend, which again are available to resist over-tensioning.
  • the hooks of the hook-strip screen are used to retain the sheet of wire cloth in a shaker machine in manner know per se.
  • FIG. 1 is a plan view of a wire mesh filter screen
  • FIG. 2 is a plan view of a hook-strip screen, stretched over a radius
  • FIG. 3 is a perspective view of a wire cloth roll, partly unrolled
  • FIG. 4 is a plan view of a rectangular panel cut from the roll with the warp and weft wires shown to an enlarged scale in a scrap view;
  • FIG. 5 illustrates the orientation of rectangular mesh openings relative to the direction of solids flow over the screen, which hitherto has been held to be the preferred orientation for the openings in the weave of such cloth;
  • FIG. 6 is a plan view of an integral rectangular screen showing how rectangular mesh cloth has (historically) been orientated relative to the support frame;
  • FIG. 7 shows how two frames such as shown in FIG. 6 can be covered using a single 66′′ wide cloth using a preferred method of manufacture
  • FIG. 8 shows how a length of 48′′ wide rectangular mesh wire cloth can be used in the preferred manufacturing process in which two screens are made at the same time in a single jig.
  • a standard 230 mesh screen cloth has the following features:
  • a screen has been manufactured in accordance with the invention, which has larger warp wires than weft wires.
  • the modified cloth has the following features:
  • the wires of the modified 230# mesh cloths provide a slightly elongated wire aperture (having a 1:1.1 aspect ratio). This does not compromise the cut point significantly.
  • the overall nominal cut point would be 76.3 rather than 74 (by the equivalent spheres method).
  • the conductance of the modified mesh is probably decreased from 1.17 kD/mm to 1.07 kD/mm. However this is offset by the fact that the warp wires have 22% greater cross-sectional area, which significantly prolongs the life of the screen.
  • An alternative modified 230# mesh cloth has the following attributes:
  • wire apertures are square.
  • a wire cloth having a generally square weave (or mesh) contains substantially as many weft wires per unit length as there are warp wires per unit length. Where the cloth is to have a rectangular mesh case there are usually more warp wires per unit length than weft per unit length, because the time to weave a roll of wire-cloth is dependant upon the number of weft wires.
  • a 48′′ wide rectangular mesh wire cloth is illustrated in FIG. 4 .
  • rectangular mesh cloth is employed in the manufacture of a rectangular integrated screen, it is generally believed that in order to achieve optimum solids conveyance and de-blinding the rectangles in the mesh should be aligned with their longer dimension parallel to the direction of solids flow over the screen, as shown in FIG. 5 .
  • the frame has a plurality of regularly arranged similar sized smaller rectangular openings, the longer dimensions of which are parallel to the length dimension of the frame, the solids flow will normally be parallel to the length dimension of the frame, and this means that for a rectangular mesh cloth stretched over rectangular openings the warp wires should run the length of the rectangular openings, as shown in FIG. 6 .
  • a common screen size is of the order of 42′′ ⁇ 30′′ and if 48′′ wide cloth is to be used so that the warp wires extend across the 30′′ dimension the cloth has to be orientated relative to the frame so that the 48′′ width extends across the 30′′ width of the frame, and there will be a lot of waste cloth to be cut away from the two longer edges of the frame after bonding.
  • Such screens are preferably manufactured using a jig as described in GB Patent 2,382,037.
  • This jig essentially requires a single sheet of wire cloth 66′′ by 48′′ to be laid over two frames, arranged side by side in the jig as illustrated in FIG. 7 .
  • FIG. 8 illustrates the method of making a screen as proposed by the present invention which allows 48′′ wide woven wire cloth to be employed.
  • the 48′′ wide cloth is cut to 66′′ length, and laid over the two side by side frames in the jig, with the warp wires perpendicular to the length dimension of the frames and therefore perpendicular to the longer dimension of each of the smaller rectangular openings in the frames.
  • the invention thus has the advantage of enabling fully functional and long-life screens to be made using standard 48′′ wide woven wire cloth.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Filtering Materials (AREA)
  • Combined Means For Separation Of Solids (AREA)
  • Gasification And Melting Of Waste (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Filters For Electric Vacuum Cleaners (AREA)
  • Centrifugal Separators (AREA)
  • Glass Compositions (AREA)
  • Separation Of Solids By Using Liquids Or Pneumatic Power (AREA)
  • Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
  • Silicon Polymers (AREA)
  • Ceramic Products (AREA)
  • Filtration Of Liquid (AREA)
US10/543,042 2003-04-12 2004-04-07 Filtering screen Active 2025-07-30 US8104623B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US13/333,421 US8246771B2 (en) 2003-04-12 2011-12-21 Filtering screen

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB0308475.3 2003-04-12
GBGB0308475.3A GB0308475D0 (en) 2003-04-12 2003-04-12 Filtering screen
PCT/GB2004/001527 WO2004089558A2 (fr) 2003-04-12 2004-04-07 Filtre tamis

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US13/333,421 Division US8246771B2 (en) 2003-04-12 2011-12-21 Filtering screen

Publications (2)

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US20060081529A1 US20060081529A1 (en) 2006-04-20
US8104623B2 true US8104623B2 (en) 2012-01-31

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Application Number Title Priority Date Filing Date
US10/543,042 Active 2025-07-30 US8104623B2 (en) 2003-04-12 2004-04-07 Filtering screen
US13/333,421 Expired - Lifetime US8246771B2 (en) 2003-04-12 2011-12-21 Filtering screen

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Application Number Title Priority Date Filing Date
US13/333,421 Expired - Lifetime US8246771B2 (en) 2003-04-12 2011-12-21 Filtering screen

Country Status (11)

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US (2) US8104623B2 (fr)
EP (1) EP1615728B1 (fr)
AT (1) ATE465824T1 (fr)
CA (1) CA2513413C (fr)
DE (1) DE602004026853D1 (fr)
DK (1) DK1615728T3 (fr)
EA (1) EA007130B1 (fr)
GB (2) GB0308475D0 (fr)
MX (1) MXPA05008075A (fr)
NO (1) NO330694B1 (fr)
WO (1) WO2004089558A2 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0427756D0 (en) * 2004-12-18 2005-01-19 United Wire Ltd Improvements in and relating to sifting screens
CN101869889B (zh) * 2010-06-22 2012-07-04 成都大宏立机器制造有限公司 一种编织筛网组合式振动筛
CN102872993B (zh) * 2012-10-12 2014-09-24 湖州博力涂装机械有限公司 金属丝编织网防蚀涂装设备
RU186145U1 (ru) * 2018-08-08 2019-01-11 Общество с ограниченной ответственностью "Научно-производственное объединение "Центротех" (ООО "НПО "Центротех") Каркас виброрамы вибросита
IT201800010762A1 (it) * 2018-12-03 2020-06-03 Saati Spa Tessuto ad alta prestazione per filtri di separazione acqua/gasolio.

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2211081A (en) 1936-04-13 1940-08-13 Peter S Sinclair Dandy roll and cylinder mold
US2425235A (en) * 1943-07-16 1947-08-05 Kenlea Mfg Company Filter
US3012674A (en) 1958-06-16 1961-12-12 Hoppe Gerhard Oscillating screen structure
US3094302A (en) 1959-10-28 1963-06-18 Continental Copper & Steel Ind Wire screen sealing system
US5944197A (en) * 1997-04-24 1999-08-31 Southwestern Wire Cloth, Inc. Rectangular opening woven screen mesh for filtering solid particles
US6305549B1 (en) 1999-07-06 2001-10-23 Southwestern Wire Cloth, Inc. Vibrating screen assembly of dissimilar materials
US20020023883A1 (en) * 1999-11-03 2002-02-28 Adams Thomas C. Lost circulation fluid treatment
GB2382037A (en) 2001-11-10 2003-05-21 United Wire Ltd A tensioned screen for separating particles in a vibrating machine

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2211081A (en) 1936-04-13 1940-08-13 Peter S Sinclair Dandy roll and cylinder mold
US2425235A (en) * 1943-07-16 1947-08-05 Kenlea Mfg Company Filter
US3012674A (en) 1958-06-16 1961-12-12 Hoppe Gerhard Oscillating screen structure
US3094302A (en) 1959-10-28 1963-06-18 Continental Copper & Steel Ind Wire screen sealing system
US5944197A (en) * 1997-04-24 1999-08-31 Southwestern Wire Cloth, Inc. Rectangular opening woven screen mesh for filtering solid particles
US6305549B1 (en) 1999-07-06 2001-10-23 Southwestern Wire Cloth, Inc. Vibrating screen assembly of dissimilar materials
US20020023883A1 (en) * 1999-11-03 2002-02-28 Adams Thomas C. Lost circulation fluid treatment
GB2382037A (en) 2001-11-10 2003-05-21 United Wire Ltd A tensioned screen for separating particles in a vibrating machine

Also Published As

Publication number Publication date
DE602004026853D1 (de) 2010-06-10
EP1615728B1 (fr) 2010-04-28
US20120152452A1 (en) 2012-06-21
GB0308475D0 (en) 2003-05-21
US20060081529A1 (en) 2006-04-20
ATE465824T1 (de) 2010-05-15
MXPA05008075A (es) 2005-12-15
WO2004089558A3 (fr) 2005-03-24
GB0407899D0 (en) 2004-05-12
GB2401803B (en) 2005-08-03
EA200501608A1 (ru) 2006-02-24
EA007130B1 (ru) 2006-06-30
GB2401803A (en) 2004-11-24
NO20053475L (no) 2005-12-21
US8246771B2 (en) 2012-08-21
DK1615728T3 (da) 2010-07-19
EP1615728A2 (fr) 2006-01-18
WO2004089558A2 (fr) 2004-10-21
NO20053475D0 (no) 2005-07-15
CA2513413A1 (fr) 2004-10-21
NO330694B1 (no) 2011-06-14
CA2513413C (fr) 2012-12-18

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